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Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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Animal Nutrition 2024年第1期16卷 422-428页

作者： Edwin t.Moran Michael R.Bedford Poultry Science department Auburn University AB Vista Woodstock Court Blenheim Road

Phytin is the Ca2+-Mg2+-K+salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca2+. Even at low gastric pH,phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca2+near the enzyme?s active site further stabilizes its newly formed structure. thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide?s basic amino acids;coordinating free Ca2+, destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca2+and other cations rebind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes(e.g. Ca2+, Zn2+) which reduces their structural resistance to autolysis and ability as co-factors(e.g. Zn2+) to increase enzyme activity. goblet cells initially employ Ca2+as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca2+is progressively displaced by Na+to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer（USWL）. Excessive removal of Ca2+from mucin by phytic acid increases its fluidity facilitating its loss from the USWL with

关键词： digestive enzyme Calcium Endogenous protein Mucin Phytin

the bumpy road of purinergic inhibitors to clinical application in immune-mediated diseases

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Neural Regeneration Research 2024年第6期19卷 1206-1211页

作者： Matihias t.Wyss Christine Heuer Marina Herwerth Institute of Pharmacology and toxicology University of Zurich Neuroscience Center Zurich (ZNZ) University of Zurich and ETH Zurich 3. Neurology Department University Hospital of Zurich

Purinergic signaling plays important roles throughout the body in the regulation of organ functions during and following the disruption of homeostasis. this is also reflected by the widespread expression of two families of purinergic receptors(P1 and P2) with numerous subtypes. In the last few decades, there has been increasing evidence that purinergic signaling plays an important role in the regulation of immune functions. Mainly, signals mediated by P2 receptors have been shown to contribute to immune system-mediated pathologies. thus, interference with P2 receptors may be a promising strat.gy for the modulation of immune responses. Although only a few clinical studies have been conducted in isolated entities with limited success, preclinical work suggests that the use of P2 receptor inhibitors may bear some promise in various autoimmune diseases. despite the association of P2 receptors with several disorders from this field, the use of P2 receptor ant.gonists in clinical therapy is still very scarce. In this narrative review, we briefly review the involvement of the purinergic system in immunological responses and clinical studies on the effect of purinergic inhibition on autoimmune processes. We then open the aperture a bit and show some preclinical studies demonstrating a potential effect of purinergic blockade on autoimmune events. Using suramin, a non-specific purinergic inhibitor, as an example, we further show that off-target effects could be responsible for observed effects in immunological settings, which may have interesting implications. Overall, we believe that it is worthwhile to further invest.gate this hitherto underexplored area.

关键词： autoimmune diseases neurological disorders purinergic system P2 receptor inhibitors suramin

distribution, health and ecological risk assessments of trace elements in Nigerian oil sands

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Acta geochimica 2024年第1期43卷 59-71页

作者： Odunayo t.Ore Festus M.Adebiyi department of Chemistry Obafemi Awolowo UniversityIle-Ife 220005Nigeria department of Chemical Sciences Achievers UniversityOwoNigeria

the Nigerian oil sands represent the largest oil sand deposit in Africa, yet there is little published information on the distribution and potential health and ecological risks of trace elements in the oil resource. In the present study, we invest.gated the distribution pattern of 18trace elements(including biophile and chalcophile elements) as well as the estimated risks associated with exposure to these elements. the results of the study indicated that Fe was the most abundant element, with a mean concentration of 22,131 mg/kg while Br had the lowest mean concentration of 48 mg/kg. the high occurrence of Fe and ti suggested a possible occurrence of ilmenite(Fe tiO_(3)) in the oil sands. Source apportionment using positive matrix factorization showed that the possible sources of detected elements in the oil sands were geogenic, metal production, and crustal. the contamination factor, geo-accumulation index, modified degree of contamination, pollution load index, and Nemerow pollution index indicated that the oil sands are heavily polluted by the elements. Health risk assessment showed that children were relatively more susceptible to the potentially toxic elements in the oil sands principally via ingestion exposure route(HQ > 1E-04). Cancer risks from inhalation are unlikely due to CR t ingestion and dermal contact pose severe risks(CR > 1E-04). the high concentrations of the elements pose serious threats due to the potential for atmospheric transport, bioaccessibility, and bioavailability.

关键词： Biophile Chalcophile Oil sand Risk assessment trace element

Nonlinear-Optical Analogies in Nuclear-Like Soliton Reactions:Selection Rules,Nonlinear tunneling and Sub-Barrier Fusion–Fission

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Chinese Physics Letters 2024年第8期41卷 1-7页

作者： t.L.Belyaeva V.N.Serkin Universidad Autonoma del Estado de Mexico Av.Instituto Literario 100C.P.50000TolucaMexico Benemerita Universidad Autonoma de Puebla Av.4 Sur 104C.P.72001PueblaMexico

the main goal of our study is to reveal unexpected but intriguing analogies arising between optical solitons and nuclear physics,which still remain hidden from *** consider the main cornerstones of the concept of nonlinear optics of nuclear reactions and the well-dressed repulsive-core *** the base of this model,we reveal the most intriguing properties of the nonlinear tunneling of nucleus-like solitons and the soliton selfinduced sub-barrier transparency *** describe novel interesting and stimulating analogies between the interaction of nucleus-like solitons on the repulsive barrier and nuclear sub-barrier *** main finding of this study concerns the conservation of total number of nucleons(or the baryon number)in nuclear-like soliton *** show that inelastic interactions among well-dressed repulsive-core solitons arise only when a“cloud”of“dressing”spectral side-bands appears in the frequency spectra of the *** property of nucleus-like solitons is directly related to the nuclear density distribution described by the dimensionless small shape-squareness *** the Fourier spectra of nucleus-like solitons are similar to the nuclear form *** show that the nuclear-like reactions between well-dressed solitons are realized by“exchange”between“particle-like”side bands in their spectra.

关键词： solitons soliton Nonlinear

Effects of layer interactions on instantaneous stability of finite Stokes flows

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： Chen ZHAO Zhenli CHEN C.t.MUtASA dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

the stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. the oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. the effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. the growth rates of two most unstable modes when δ t equal, and δ = δ*/h*, where δ*and h*are the Stokes-layer thickness and the half height of the channel, respectively. However, their vorticities are different. the vorticity of the most unstable mode is symmetric, while the other is asymmetric. the Stokes-layer interactions have a destabilizing effect on the most unstable mode when δ d have a stabilizing effect when δ > 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. the effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. the energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. the effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

two-dimensional atomically thin Pt layers on MXenes: the role of electronic effects during catalytic dehydrogenation of ethane and propane

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Nano Research 2024年第3期17卷 1251-1258页

作者： Zhe Li tobias K.Misicko Fan Yang Xiaopeng Liu Zhenwei Wu Xiaoyang gao tao Ma Jeffrey t.Miller daniela S.Mainardi Collin d.Wick Zhenhua Zeng Yang Xiao Yue Wu department of Chemical and Biological Engineering Iowa State University618 Bissell RoadAmesIA 50011USA Institute for Micromanufacturing Louisiana Tech University505 Tech DriveRustonLA 71272USA davidson School of Chemical Engineering Purdue University480 Stadium Mall DriveWest LafayetteIN 47907USA Michigan Center for Materials Characterization University of Michigan2800 Plymouth RdAnn Arbor MI 48109USA College of Engineering and Science Louisiana Tech UniversityRustonLA 71272USA

Atomically thin Pt nanolayers were synthesized on the surface of Mo2tiC2 MXenes and used for the catalytic dehydrogenation of ethane and propane into ethylene and propylene,two important chemicals for the petrochemical *** compared with Pt nanoparticles,the atomically thin Pt nanolayer catalyst showed superior coke-resistance(no deactivation for 24 h),high activity(turnover frequencies(tOFs)of 0.4–1.2 s^(-1)),and selectivity(>95%)toward ethylene and *** unique Pt nanolayer has a similar geometric surface to Pt nanoparticles,enabling the invest.gations of the electronic effect on the catalytic performance,where the geometric effect is *** is found that the electronic effect plays a critical role in dehydrogenative product selectivity and catalyst *** metal–support interaction is found dependent on the substrate and metal components,providing wide opportunities to explore high-performance MXene-supported metallic catalysts.

关键词： MXene catalysis alkane dehydrogenation nanolayers

the Radcliffe Wave Parameters from data on Open Star Clusters

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Research in Astronomy and Astrophysics 2024年第3期24卷 106-109页

作者： V.V.Bobylev A.t.Bajkova Pulkovo Astronomical Observatory St-Petersburg 196140Russia

A spectral analysis of the vertical positions and velocities of 374 open star clusters(OSCs)was carried *** took these OSCs from the Hunt and Reffert catalog;they have an average age of about 10 million years,and are located on the galactic plane XY in a narrow zone inclined by 25°to the galactic axis *** following estimates of the parameters of the Radcliffe wave were obtained:(a)the maximum value in periodic perturbations of vertical coordinates Z_(max)=92±10pc with the wavelength of these perturbations λ_(z)=4.82±0.09 kpc;(b)the maximum value of the velocity of vertical disturbances Wmax=4.36±0.12km s^(-1) with disturbance wavelengthλ_(W)=1.78±0.02 *** that the results of the vertical velocity analysis are first-class in accuracy and completely new.

关键词： (galaxy) local interstellar matter-galaxy structure-(galaxy) solar neighborhood

Voids size distribution in gelled waxy crude oil under dynamic and static cooling

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Petroleum Research 2024年第1期9卷 109-114页

作者： girma t.Chala Shaharin A.Sulaiman department of Mechanical Engineering(Well Engineering) International College of Engineering and ManagementP.O.Box 2511C.P.O Seeb 111MuscatOman department of Mechanical Engineering Universiti Teknologi PETRONASBandar Seri Iskandar37500TronohPerakMalaysia

Waxy crude oil is known for its high wax contents that can potentially result in gelling following sufficient cooling of the transportation line in the subsea bed at offshore *** gelling over the entire lines requires an accurately predicted restart pressure to restart the clogged and idle ***,the common way of predicting the restart pressure has been reported to result in over-designed and predicted piping *** research findings evidenced the formation of voids which would reduce the restart pressure *** study conducted in this paper is aimed at invest.gating the voids size distribution in gelled crude oil across and along transportation *** of experiments simulating crude oil transportation during both static and dynamic cooling were *** gelled crude oil below the pour point temperature was then scanned using a Magnetic Resonance Imaging(MRI)system to detect the voids *** resulting voids at each scanning cross-section were quantified,and their distributions were *** was observed that dynamic cooling had minimal impacts on the voids size difference along the pipeline with the difference in voids areas within 10 mm^(2) to be twice and uniform for the entire flow rates ***,voids size in statically cooled waxy crude oil was found to be highly distributed with a maximum of 6 voids size distribution in 10 mm2 *** low-end temperature had the highest size difference while the difference was decreasing with higher end *** study shows that the voids amount in dynamically cooled waxy crude oil could also be estimated with lower numbers of cross-sectional voids ***,the higher cross-sectional voids detection is recommended while estimating voids in statically cooled waxy crude oil.

关键词： gelled crude oil Voids size distribution dynamic cooling Static cooling

进一步改善城市网-厂-水体污水系统升级改造和运行效率的四点看法

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给水排水 2024年第4期50卷 137-144页

作者：曹业始 KROISS H VAN LOOSdRECHt M dAIggER g t 中持新概念环境发展宜兴有限公司宜兴214213 维也纳工业大学水质和资源管理研究所奥地利维也纳1040 代尔夫特理工大学生物技术系荷兰代尔夫特2629HZ 密歇根大学土木和环境工程系美国密歇根州48109

2022年,《深入打好城市黑臭水体治理攻坚战实施方案》发布,要求努力解决河流雨后黑臭和雨季河流断面水质下降问题,力争到2025年,进水BOd浓度高于100毫克/升的城市生活污水处理厂规模占比达90%以上,城市生活污水集中收集率达到70%以上。... 详细信息

2022年,《深入打好城市黑臭水体治理攻坚战实施方案》发布,要求努力解决河流雨后黑臭和雨季河流断面水质下降问题,力争到2025年,进水BOd浓度高于100毫克/升的城市生活污水处理厂规模占比达90%以上,城市生活污水集中收集率达到70%以上。水行业正面临着防止雨后河流返黑和改善雨季河流水质等新任务。因此,结合近年来成绩、实践和欧美的经验教训,提出和讨论了与进一步改善网-厂-水体城市污水系统升级改造及运行效率相关的四个问题:分流制管网有没有外(雨)水入侵和溢流、污水处理厂的进水浓度应多高、为什么部分污水处理厂需局部扩容、为什么污水管道中流速低于自净流速,并在此基础上,对相关工作提出了建议。

关键词：城市污水系统污水管网外水入侵雨水溢流污水浓度污水处理厂扩容水环境容量

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